Gas flow control valve



United-States Patent Richard Glll'llllll 2] lnyenk"PrimaryExaminer-Robert Nilson 2664 Russmar Drive, San Diego,'CallfornlnAttorney-R. S. Sciascia, E. F. Johnston and T. G. Keough 92123 [2]]Appl. No. 749,097 M [221 Ned July 1968 ABSTRACT: The disclosed inventionrelates to gas flow con- Patemed trol valves used by divers wherever aprecisely regulated gas H mixture volume is required. This regulation isnecessary with semiclosed gas or possibly, closed gas breathing systemsor [54] ZALVE systems other than those using demand-type regulators Anin- I g herent requirement of such systems is that a constant volume US.Cl. of gas be precisely valved according to the needs of the dive]:137/599 In the instant invention this valving is provided by a selectiveInt. Cl. .m. valve unit ensunng any one of several gas-volume combula.[50] Field ofSureh l37/63R, to be switched to the valves assembly, Inaddition, a 599, 555 bypass valve unit is included giving a free flow ofgas through the valve mechanism when the diver is descending, working{56] Rem'mm Cited 1 very hard, or when an emergency arises Constructionof the UNITED TATE P E valve mechanism from noncorrosive metals witheasily 2,457,779 12/1948 Kincaid 137/599 identified controls, enablesreliable one-hand operation of the 3,351,089 I l/ 1967 Garrahan l37/599valve mechanism under adverse conditions.

250 5 25b 506 /7 I6 230 24 //g //T2/ L2 I I I l 24 Patehted NoJv. 24,1,970 v 'Sheet Z of4 I N VEN TOR.

R/CHAR GARRAHA/V BY A T TOR/VL Y5 Pate nted}; Nev; 24, 1970 Sheet FIG.

INVENTOR. RIC 4RD GARRAHA/V ATTORNEYS Patentcd Nov. 24, 1970 Sheet 1 of4N A Rm Wm m m /M 0 VA MT W6 /T "Fla. 7

. 1 GAS rLow CONTROL VALVE STATEMENTOF GOVERNMENT INTEREST The inventiondescribed herein may be manufactured and used by or for the Governmentof the United States of America for governmental purposes without the apayment of any royalties thereon or th'erefon- BACKGROUND or THEINVENTION Divers requiring a constant volume of a particular gas mixtureat varying depths are confronted, with the problem of being able toprovide the proper amount of gas under varying conditions, that is tosay, depth and the amount of divers physical exertion call for differentamounts of gas. Existing delicate, elaborate valving mechanisms requirea divers full attention when selecting the proper gas-volume mixtureand,

thusly detract from the divers work.-In addition, these mechanisms areconstructed to operate only within a predetermined range of operationsand are not readily modified for service in other situations governed bydifferent physical outputs or depths. At great depths or under poorvisibility conditions, a diver additionally is hampered by the fact thatvisual adjustment is impossible and diving mittens, for protection fromthe cold .of the surrounding water, prevent the diver from determiningaparticular valve setting.

All the above can result in an adverse psychological impact I on thediver that is reflected in the execution of his work assignment.

,THBSUMMARY or THE INVENTION The present invention is directed toproviding a reliablevalve mechanism for controlling the volume of gaspassed from a diver-carried source of gas, or a remote source, through asemiclosed or closed underwater breathing system. The mechanism includesan essentially rectangularly shaped housing mechanism constructed of anoncorrosive material in which a bypass valve unit is disposed includinga traverse duct linking a gas inlet to 'a gas outlet and 'areciprocating piston changing of the threaded screws having orifices ofone size to screws having orifices of different sizes to allow variationof the passed volume of gas as conditions change; Adequate sealingaround the bypass valve unit, selector valve unit, and removable plugensures a transfer of an uncontaminated, constant supply of airthroughthe valve. A large, flat bypass lever actuating the bypass valve unit, aknob-mounted projecting portion, and'a detenton the selector valve un'itensure foolproof operation underthe most adverse conditions.

Therefore, it is the prime object of the instant invention to provide avalve mechanism that passes a'par'ticular volume of as. g Another objectof the invention is to provide a valve mechanism rugged and foolproofunder the most adverse conditions.

Further object of the invention is to provide a valve mechanism readilymodified for delivering varying amounts of gas volume depending upon theenvironmental conditions by means of replaceable orifice members.

Still another object is to provide a valve mechanism so compact andreliable that a diver can operate the mechanism with one hand withoutsubstantial detraction from a work assignment.

These and other objects to the invention will become readily apparentfrom the drawings and ensuing description in which:

FIG. 1 is an isometric depiction of the invention in an operativeenvironment with a sample semiclosed breathing unit worn by a diver;

FIG. 2 is an isometric view of the valve mechanism;

FIG. 3a is a cross-sectional view generally taken along lines 3-3 inFIG. 2 in which the bypass valve unit is closed and blocking gas flow,in addition, the traverse passageway is shown in overlappingrelationship to the traverse duct;

' FIG. 3b is a cross-sectional view generally taken along lines 3-3 inFIG. 2 in which the bypass valve unit is open and permitting gas freeflow plus showing the traverse passageway in an overlapping relationshipto the traverse duct;

FIG. 4a is a cross section of the taken along lines 4-4 in FIG. 2 inwhich the selector valve unit is passing gas through amiddle one of theegress ducts;

FIG. 4b" is a crosssection of the invention taken along lines 4-4 inFIG. 2 but furtheremphasizing the position of the port in the gasket asit is rotated from the middle one to a far end one of the egress ducts;

FIG. 4c is a cross-sectional view taken along lines 4-4 in FIG. 2setting forth the positioning of the port in the gasket on the far oneof the egress ducts and the blocking of the other ducts by the gasket}FIG. 5 sets forth the orientation of the egress ducts in the secondcavity;

FIG. 6 is a top view of the gland nut; and

FIG. 7 shows a crosssection of a threaded member.

PREFERRED EMBODIMENT OF THE INVENTION Referring now to the drawings,FIG. ldepicts the diver wearing a typical semiclosed circuit underwaterbreathing apparatus including a pair of breathing bags carried adjacentthe chest connected to a C0 absorption canister, not shown, supported onthe'back of the diver. The invention, a gas flow control valve 10, ismounted on a support plate 10a connected on the front of a vest thatforms the support for the semiclosed rebreathing circuit. A gas inletpipe 10b extends to a remotely located constant gas supply source or aback pack supply, not shown for the sake of simplicity in the drawings.An outlet tube 100 passes the proper volume of gas mixtures asdetermined by the gas flow control valve to the breathing bags at apoint between the inhale bag and the canister.

In a preferred embodiment, a housing member 15 is constructed of brass,or a similarly, relatively noncorrosive material, capable ofwithstanding the abuses and pressureextremes attendant divingoperations. The housing member is machined to enclose a bypass valveunit 20, enabling a free flow of gas, and a selector valve unit 30,providing varied volumes of gas through the mechanism. An inlet recess16 and an outlet recess 17 are formed in the housing member and servesas a gas inlet and a gas outlet for both units. Both recesses areinternally threaded in a manner corresponding to the inlet and outlettubes to facilitate a watertight connection to the rest of the breathingsystem.

Turning now to FIG. 3a and FIG. 3b, the bypass valve unit is disposed ina first threaded bore 21 in the housing member and a traverse duct 22extends from thebore to the outlet recesses via the bore. A bypass glandnut 23 is provided having threads corresponding to those tapped withinthe bore and carries a plurality of sealing "0 rings 23a, 23b, and 23c.Radially extending holes 24 are drilled in the gland nut and are sizedand positioned for alignment with the traverse ducts. A bypass valvestem 25, carried in the gland nut, is shaped with a hollowtube-shaped'bypass conduit 25b around the shank of the stern and alsomounts a sealing ring 25a on an inner section that is forcibly heldagainst the innermost rim of the gland nut by a helical spring 26mechanically cooperating to function as a biasing element in the bypassvalve unit since the mechanical coaction of the helical spring, bypassvalve stem,

sealing ring, and gland nut normally blocks any gas flow from the inletrecess to the outlet recess, see FIG. 3a.

A relatively large, flat bypass valve lever 27 extends alongsubstantially one-half of a longitudinal side of the housing member andis secured to the housing member by pin 27a, to rest in contact with thebypass valve stem. Because of its large flat surface, confusion withother elements is minimized. Upon pressing the bypass valve lever withsufficient force to overcome the biasing effect of the helical spring,the bypass valve unit permits a free flow of gas from the inlet recessvia the bypass conduit, radially extending holes, and traverse duct,note the gas flow arrows in FIG. 3b. Merely releasing the applied forceon the bypass lever allows the helical spring to return the sealing ringto its sealed position against the gland nut to once again block theflow of gas between the inlet and the outlet recess.

The housing member is additionally formed with a bored traversepassageway 49 separate and distinct from the traverse duct that is fedgas through a port 49' in fluid communication with inlet recess 16. Thepassageway terminates at a traverse passageway outlet 49a in a secondcavity 31, and the housing is further formed with a plurality of egressducts 50a, 50b, and 50c. Selective variation of the gas volume passedtherethrough is the function of selector valve unit 30 and includesrotatable and reciprocal selector valve components 30a and gasrestricting threaded members 52. The threaded members are screwed intothe ducts and the transfer of gas to a third cavity, threaded bore 51.

A selector gland collar 32 is force-fitted or brazed inside the entranceto the second cavity and a selector gland nut 33 mounting ring seals 33'and 33", is screwed into the collar. Four, relatively deep, curvedrecesses 33a, 33b, 33c, and 33d are formed on the nuts outer surface ina 90 spaced relationship and ball-rider surfaces 34a, 34b, 34c, and 34dare interposed between the curved recesses, the purpose of which will bepointed out below.

A valve piston 35 extends through the gland nut to the interior of thesecond cavity and terminates in a dishlike gas channeling portion 36.The channeling portion is shaped with a single laterally extending boredchannel 37, being in communication with a single inwardly,longitudinally-extending throat 38 and a pair of oppositely disposedholes 38a and 38b (for pressure equalization inside the mechanism).Adjacent the inwardmost side of the channeling portion, a neoprenegasket 39 is carried having a lateral gasket port 40 disposed in acoincident relationship with respect to throat 38.

At the upward end of the valve piston an indicator knob 41, mounting aprojecting portion 41a, is brazed or screwed onto the piston. On itsinner surface the knob is provided a pair of cup-shaped chambers spaced180 apart for containing a pair of detent balls 42 and 43. A secondhelically-shaped biasing spring 35a is wound around the valve piston andis constructed to force the indicator know knob toward the selectorgland nut to securely position the moveable selector valve components inposition when the detent balls rest in the curved recesses, that is tosay, the moveable components are biased to remain in one of fourpositions spaced 90 from one another.

the knob is rotated, the detent balls ride out of the curved recessesand onto the ball rider surfaces arcuately disposed between therecesses, see FIG. 4b. The ball's riding out of the recesses axiallyovercomes the biasing spring and displaces the valve piston to raise thegasket port from a particular egress duct. When the balls fall intoadjacent arcuately disposed curved recesses, with an audible snap" andan impulse heard and felt by a diver, the gasket port and aligned throatare placed immediately adjacent another one of the egress ducts. Thesnap" and projecting portion 410 positively indicate to a diver that adesired valve position providing a gas transfer rate has been selected.By noting FIGS. 40, 4b, and 4c this transfer can be seen for thechanging of gas fiow communication from egress duct 50b to 500, the knobbeing turned in a counterclockwise direction.

The egress ducts, 50a, 50b, and 50c, terminate at their innennost endadjacent gasket 39 in the configuration of FIG. 5. A blank space 50d isprovided to enable the operator to shut off the selector valve unit byrotating the gasket port to a position adjacent the blank space via theselector knob. As mentioned before, at the other end of the three ductsare located three separate threaded members 52, each enclosing an axialorifice of different diameter in communication with a third cavity 51.The diameters are different from one another to allow only apredetermined amount of gas to pass therethrough, the amount beingdetermined by the particular diameter, the pressure of the externalsource of gas, and the surrounding pressure.

The third cavity is closed and sealed by a plug 53 to form a mixingchamber 54. From a mixing chamber the chamber passageway 54a links theoutlet recess to the inlet recess via the traverse passageway, selectorvalve unit, egress ducts, and mixing chamber.

FIGS. 4a, 4b, and 40, show the transfer of gas from the traverse passageoutlet 490 through the moveable selector components, egress ducts,threaded members, and to the outlet recess. The flow arrows in FIG. 4ashow a transfer of a first volume of gas through egress duct 50b and itsassociated threaded member while FIG. 4b, depicts the axially displacedposition of the moveable selector valve components as the knob isrotated counterclockwise and balls 42 and 43 are carried on ball-ridersurfaces 340 and 340 respectively.. The gasket port 40 has been pulledaway from egress duct 50b and is positioned arcuately midway betweenegress ducts 50b and 500. Unimpeded flow through all the ducts nowprevails, but, since switching time is relatively short, this matterslittle.

FIG. 40 shows the gasket port adjacent egress duct 500, with the gasketagain sealing off the other ducts to allow only a measured amount of gasto flow through duct 50c.

Noting FIG. 1, operation of the invention is easily performed by a diverwhen a changed supply of gas is needed. As shown in the drawings, thediver need only raise his left hand to the gas flow control valve andpress the bypass lever to effect the mechanical coaction shown in FIG.3b to permit a free flow of gas through the mechanism. A free flow ofgas may be necessary under strenuous diving working conditions or if thediver is descending relatively rapidly.

Precise lesser volumes of gas are delivered to the diver by merelyturning the indicator knob without undue distraction.

As explained above, turning of the knob will align the gasket port witha desired egress duct containing a particular threaded member to deliverthe correct amount of gas. The projecting portion 41a enables the diverto know the selector valve units position without having to look at thevalve mechanism and the position of the mechanism can be determined evenwhile wearing heavy diving mittens.

When diving at depths, loss of visibility and extreme cold imposeslimitations on a divers ability to carry out assigned tasks. Heavyinsulating mittens, while affording some relief from the cold, furtherdiminish a divers sense of touch to the extent that selection of aproper small knob or switching position is impossible. The presentinvention compensates for visibility and sensory limitations byproviding a relatively large bypass lever and a single, unmistakablerotatable selector knob, both easily identifiable and arranged forsingle hand operation. As the selector valve knob is rotated, the detentballs ride out of one set of curved recesses and snap into another setto further apprise a diver of the proper selector valve setting. Thusly,the invention provides an improvement over existing diving valvemechanisms ensuring a reliability heretofore unobtainable.

Modifications can be made in view of the above teachings within thescope of one skilled in the art, and the disclosed inventive concept isto be construed as taken to include such modifications and not to beinterpreted as applying to only specific embodiment set out above.

a traverse duct linking said inlet recess to said outlet recess;

reciprocating means carried in said first cavity having an elementconfigured to normally block said traverse duct;

a hinged bypass valve lever longitudinally extending along a substantialportion of said housing member being sized and positioned to ensure asingle handed displacement of said reciprocating means and said elementto selectively enable a free flow of said gas through said traverseduct;

a selector valve unit disposed in said housing member including;

a traverse passageway linking said inlet recess to said second cavity;

a plurality of egress ducts each adapted to allow different rates offlow of said gas therethrough linking said second cavity to said outletrecess;

an axial valve piston extending from said second cavity to the exteriorof said housing member mounting on its inner end a disk-shaped gaskethaving a lateral gasket port formed to ensure gas flow communicationfrom said second cavity to said outlet recess upon being aligned with asingle one of said egress ducts; and

' means for simultaneously imparting axially reciprocal motion androtational motion to said valve piston to axially displace androtationally position said gasket port in realinement with a selectivelydifferent one of said egress ducts to ensure a different rate of saidgas flow communication, both said bypass valve unit and said selectivevalve unit are further provided with external portions configured andoriented to ensure reliable one handed operation under adverseconditions. 2. A valve mechanism according to claim 1 further includingmeans for limiting the volume of said gas passed through each of saidegress ducts being disposed therein and each having different sizedorifices.

3. A valve mechanism according to claim 2 in which the means forimparting simultaneous axially reciprocal motion and rotational motionincludes a helical biasing spring axially disposed about the axial valvepiston and an indicator knob carrying ball members opposed to arcuatelydisposed curved recesses to impart said reciprocal motion upon beingrotated, upon said realinement, snapping said gasket port in said gasflow communication with a different one of said egress ducts.

4. A valve mechanism according to claim 3 further including a thirdcavity formed in said housing member and linking said egress ducts tosaid gas outlet recess, the limiting means having their outer surfacesexposed therein and a removable plug closing said third cavity forpermitting exposure of said limiting means and the selectiveinstallation and removal thereof.

5. A valve mechanism according to claim 4 further including biasingmeans provided in said bypass valve unit urging said bypass valve unitto normally block said traverse duct.

6. A valve mechanism according to claim 5 further including meanscarried on an outer side of the means for simultaneously impartingaxially reciprocal motion and rotational motion for indicating therelative alinement and said realinemnt within said selector valve unit.

7. A valve mechanism according to claim 6 in which said housing memberis essentially rectangular shaped and the first, second, and thirdcavities are lateral bores.

